Monday, December 31, 2012

I apologize for the sheer inactivity here - I didn't even come by to wish people a merry Christmas/happy Hanukkah/joyous Kwanzaa. Hopefully with the new year that'll all change. And now since 2013 is upon us, I find it perfectly acceptable to run down a list of this year's revolutionary discoveries.

This year has provided several great discoveries of feathered dinosaurs. Shown to the right is Yutyrannus huali. There's an ongoing debate on its identity; some say it is a tyrannosauroid while others retaliate with the possibility of it being a carnosaur. Whether it be T. rex's granddaddy or some Chinese flesh-grazer, it weighs in at 3000lbs and is nearly 30ft long, making it the biggest dinosaur with known evidence of feathers. It proves that size doesn't necessarily correlate with the presence of feathers, being an Allosaurus-sized dinosaur. Next up on the chopping block is Sciurumimus albersdoerferi, an adorable little puffball with an almost impossible to remember specific name. Known from a juvenile originally called "Xaveropterus", Sciurumimus gave us a plot twist when it turned out not to be another compsognathid or even a coelurosaur, but actually a megalosauroid, showing that feathers weren't restricted to coelurosaurian theropods. Finally, the last outstanding feathered discovery was discovered in North America AND it was a known genus...

Ornithomimus, portrayed at the left, has long been thought to have feathers, as well as its comrades. Only now do we have proof. A new study described this year showed that several fossils of different ages had plumaceous feathers, and that only the adults had wings, perhaps for display.

South America has been a treasure trove for unusual species in the past. The largest known dinosaur Puertasaurus reuili was discovered there, as well as many other sauropod giants such as Argentinosaurus huinculensis, Futalognkosaurus dukei and"Antarctosaurus" giganteus. Theropod giants weren't excluded either, including massive carcharodontosaurs like Giganotosaurus carolinii, Mapusaurus roseae, and Tyrannotitan chubutensis, as well as the industrial-sized abelisaur Ekrixinatosaurus novasi. However, not much seems to have been uncovered in the way of non-dinosaurian giants. Sure, we know giant crocodiles, phorusrhacids, and mammals ruled the land after the non-avian dinosaurs died out, but what about during their reign? The new Aerotitan sudamericanus clears some way for (somewhat) terrestrial giants. An azhdarchid, this new pterosaur had a wingspan of at least five meters, comparable to the more aerial sea-feeding pterosaurs found in Brazil. Now you can jsut picture it invading a titanosaur's nest site, swallowing eggs and snapping up juveniles.

Speaking of South American giants, remember Titanoboa cerrejonensis? It turns out this megasnake wasn't the only giant reptile on the block. Unearthed this year was the turtle Carbonemys cofrinii, an immense giant with a shell nearly 6ft long. Though this isn't half as long as the later giant turtle Stupendemys souzai, it is still nonetheless an impressive beast, and if anything like the modern day snapping turtle, a force to be reckoned with.

Giant reptiles seem to be rather commonplace this year. This time however, we go to the extreme north of the island of Svalbard to find our next example. "Predator X" has been known since 2008, even starring in the documentary Planet Dinosaur, but only this year was its name revealed: Pliosaurus funkei, the sixth species of Pliosaurus. Whether or not its specific name is actually pronounced as "funky" is unknown to me, but it was definitely a giant at approx. 42ft long.

Another European native has also shocked us this year, but not by size, appearance, or biological weaponry (such as the disproven venomous Sinornithosaurus), but by its choice of habitat. The recently discovered mosasaur Pannoniasaurus inexpectatus is aptly named because nobody expected it to live in not saltwater, but freshwater. While other mosasaurs, such as Goronyosaurus, could have inhabited brackish water and one specimen of Plioplatecarpus (if I recall correctly) seems to have stranded into freshwater, Pannoniasaurus is the only one currently known to have lived its entire life in rivers and lakes. Some have suggested it as a sort of reptilian river dolphin, but I picture it more as a crocodile. And speaking of crocodiles...

Crocodilians of immense size seem to be a staple throughout history. Deinosuchus is immensely covered, perhaps not as much as Sarcosuchus however. Both suffer from anachronism and misplacement, the former often depicted with T. rex (wrong time, wrong place) and the latter depicted alongside Spinosaurus (once again, wrong time and wrong place). Less famous are the giant crocs of the Cenozoic and the stomatosuchids of the Cretaceous. One of our more recent crocodilians to be discovered falls under the category of Cenozoic giants. Crocodylus thorbjarnarsoni lived in Kenya from approx. 4-2mya and was longer than a pickup truck at 25ft in length, about as big as the biggest estuarine crocodiles today. What makes this monster even worse is that it may have preyed on early hominins such as Paranthropus.
Also joining the trend of large African crocodilians is Aegisuchus witmeri, the so-called "shieldcroc" shown to the above right. So far, no one has really come to a conclusion with estimates from the skull size sporadically ranging from a total length of 30-70ft. Though it appears similar to the aforementioned stomatosuchids, it is actually a member of the small family Aegyptosuchidae. No matter what estimate you go by, this was clearly a huge crocodile, possibly one of the largest in history.

Dinosaurs are probably the driving point of palaeontology, one of the most researched fields and the most attractive to the general public. As mentioned above, there have been plenty of new dinosaurs and new studies this year; so many that not each can gain its own paragraph. We now know more about the diet of Sinocalliopteryx gigas (shown at left), and we know that Microraptor zhaioanus exhibited dark iridescent plumage, similar to modern-day grackles. "Centrosaurus" brinkmani wasreassigned to its own genus Coronosaurus brinkmani, and along with the pygmy Gryphoceratops and the larger Unescoceratops, as well as Pachyrhinosaurus perotorum and Xenoceratops, added to the ever-growing diversity of ceratopsians. Dinosaurs have been named after Sauron (Sauroniops), while others haven't gained the best names (Bicentenaria argentina). We have Jurassic abelisaurs and spinosaurs (Eoabelisaurus and Ostafrikasaurus, respectively), a comparatively complete Asian spinosaur (Ichthyovenator), another new Morrison Formation sauropod (Kaatedocus), a lover of the hunt (Philovenator), and a strong-jawed heterodontosaur rediscovered in a museum collection (Pegomastax). And it even looks like dinosaurs might have stretched back to nearly 245mya, if the reexamined Nyasasaurus proves to be one (alternatively a dinosauromorph, such as a silesaurid).

There are many, many, many more new discoveries we could cover, but I think it's fitting to draw it to an end here. Happy New Year! Credits for artwork below.